[求助] 用f2py 编译f77程序报错

C=======================================================================

      SUBROUTINE DAYLEN(
     &    DOY, XLAT,                                      !Input
     &    DAYL, DEC, SNDN, SNUP)                          !Output

!-----------------------------------------------------------------------
      IMPLICIT NONE
Cf2py intent(in) doy, xlat
Cf2py intent(out) dayl, dec, sndn, snup
      INTEGER DOY
      REAL DEC,DAYL,PI,RAD,SOC,SNDN,SNUP,XLAT
      PARAMETER (PI=3.14159, RAD=PI/180.0)

!-----------------------------------------------------------------------
C     Calculation of declination of sun (Eqn. 16). Amplitude= +/-23.45
C     deg. Minimum = DOY 355 (DEC 21), maximum = DOY 172.5 (JUN 21/22).
      DEC = -23.45 * COS(2.0*PI*(DOY+10.0)/365.0)

C     Sun angles.  SOC limited for latitudes above polar circles.
      SOC = TAN(RAD*DEC) * TAN(RAD*XLAT)
      SOC = MIN(MAX(SOC,-1.0),1.0)

C     Calculate daylength, sunrise and sunset (Eqn. 17)
      DAYL = 12.0 + 24.0*ASIN(SOC)/PI
C FO 06/05/2022 Added protection to avoid day length less than 0.0
C               and greater than 24.0 hours.      
      DAYL = MIN(MAX(DAYL,0.0),24.0)
      SNUP = 12.0 - DAYL/2.0
      SNDN = 12.0 + DAYL/2.0

      RETURN
      END SUBROUTINE DAYLEN